Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1993: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1992: ¥1,400,000 (Direct Cost: ¥1,400,000)
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Research Abstract |
1. On purpose to incorporate alkali metal ion in a desolvated form into a hydrophobic solution phase, highly lipophilic and bulky perfluoroalkyl-substituted stable tetraphenylboron-ate complex were synthesized. Fluorine-substituent effects were evaluated in terms of their solubilities and decomposition rate constants in acid media. 2. Alkali metal salts of the lipophilic borate act as Lewis acid in CH_2Cl_2 to cleave (1) the C-Cl bond of triphenylmethyl chloride, giving triphenylmethyl cation and (2) the C-O bond of 1, 1, 3-trimethylspiro[indoline-2, 3'-[6]-naphtho-[2,1-b]pyrans], giving a corresponding merocyanine, accompanying color-developing. Lewis acidity of alkali metal ion was rated by the extent of induced spectroscopic shift and was discussed in terms of the ionic charge and radius. 3. Halochromic shifts induced by alkali metal salts of the lipophilic borate on 2,4,4', 6-tetramethoxyazobenzene in CH_2Cl_2 were correlated well with Lewis acidity of metal ion described above. 4. Halochromic shift induced by alkali metal salts of the lipophilic borate on 2,6-diphenyl-4-(2,4,6-triphenylpyridino)phenolate betaine was rapid rate process and difficult to be used as a measure of Lewis acidity of metal ion. 5. The observed spectroscopic shift was affected by the presence of nimute water in different manner from a solvent to another. The water concentration is, therefore, required to be precisely controlled for the quantitative rating of Lewis acidity of metal ion in a hydrophobic solution phase.
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